I need a visual description of This Locket (Its the first tab only, the SCP article is the second tab if you want to take look at it. The other 2 tabs are shit so I wouldn't recommend looking at those…)

If you've got an image, I don't think you need to have that much of a description. Just "locket pendant in the design of a key, with a heart-shaped bow" should suffice, and you can include the image by noting that it is a "safe" picture, à la SCP-931 style.

Generally for clinical tone, you just want to make sure you:

are describing things from an objective standpoint (e.g. don't use subjective words that can vary between different observers' viewpoints like "huge", "pretty", and so on)

are using concise, clear language (e.g. don't use extra-long words if they aren't necessary, don't over-embellish)

are using proper terminology that a professional in the applicable scientific field would. For example, in this case, I Googled "parts of a key" to help with the vocabulary, and this image popped up:

Generally, writers are encouraged to write up descriptions on their own; if you're unsure of how to approach writing clinically, consider taking a look how similar items are described (you can use the search bar to check for other "key", "pendant", "necklace", and other such items).

Remember to pay attention to how old an article is when deciding if you'll use it as a guide or not; you can (and should!) check article age by clicking the "History" link at the bottom of a page, and looking for the page creation date.